The invention relates to a three-phase high voltage metallic substation having three circuit breakers per two feeders and active parts housed inside single-phase metallic enclosures earthed and filled with a high dielectric strength insulating gas, notably sulphur hexafluoride, and comprising:
a first and second parallel busbar,
a plurality of single-phase cell-like cubicles with separate phases each containing a circuit breaker and disconnecting switches and earthing switches, each phase being fitted with a series of three juxtaposed cubicles electrically connected in series between the corresponding bars of the first and second busbars,
a first feeder per phase cooperating with the intermediate cubicle and one of the cubicles connected to the first busbar,
a second feeder per phase cooperating with said intermediate cubicle and the other cubicle associated with the second busbar.
According to a prior art metallic substation, described in German patent application No. 2,646,617, the circuit breakers of the different single-phase cubicles extend in a horizontal plane parallel to the two associated phase busbars. Each phase comprises a series of three juxtaposed circuit breakers located in the lower part of the substation. The busbars are located in the upper part of the substation above the feeders. Connection of the cubicles of the three phases required a special architecture which was achieved in various ways, for example, by longitudinal staggering of the series of three circuit breakers, by inclining the circuit breakers in relation to the busbars, by a triangular arrangement of the different busbar phases, or by distributing the circuit breakers over two different levels.
This architecture taught by the prior art is complicated to implement. Accordingly, an object of the present invention is to produce a substation with one and a half circuit breakers per feeder (or three circuit breakers for every two feeders) having an orderly structure, reduced overall dimensions and easy access to the various components.
The metallic substation according to the invention is characterized by the fact that all the separate phase cubicle circuit breakers are aligned longitudinally in a parallel direction to the busbars being housed in vertical enclosures located at regular intervals along the busbars, and that the lower and upper transverse connections of all the circuit breakers extend respectively in two planes parallel to the busbars.
The vertically arranged circuit breakers present two lateral connections, one upper and one lower, extending on the same side in the direction of the busbars (U-shaped circuit breaker) or in opposite directions (Z-shaped circuit breaker). All the elements which make up a cubicle are included in a transverse plane perpendicular to the busbars.
According to the preferred embodiment of the invention, the first and second circuit breakers of the cubicles of each phase present a Z-shaped structure with opposite transverse connections, whereas the third circuit breaker of each series has a U-shaped structure with transverse connections located on the busbar side. The two feeder systems are housed in the same horizontal plane parallel to that of the busbars and superposed on the cubicles, both feeders of a phase being aligned in a transverse direction and oriented in opposite directions on either side of the intermediate circuit breaker of each series of cubicles. In this case, the order of succession of the type of circuit breakers is ZZU, ZZU, ZZU.
The structure of the substation according to the invention lends itself to extension by simply extending the busbars and adding new cubicles. The busbars may be associated or separate phase extending in a common horizontal plane disposed between the two parallel planes of the lower connections of the circuit breakers.
According to an alternative embodiment, the two busbars are arranged in two parallel horizontal planes, the two bars of any one phase being superposed.
According to another alternative embodiment, the architecture of the substation can be modified in terms of the lay-out of the feeders. The feeders per phase can be located on the same side of the circuit breakers, and on the opposite side from the busbars by a simple modification to the order of succession of the type of circuit breakers, notably ZUZ, ZUZ, ZUZ .